Browsing by Subject "evolution"

Now showing 1 - 9 of 9
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    A reappraisal of the roles and relationships of neighbourhood watches: an investigation of selected neighbourhood watches in the Athlone and Annenberg areas in Cape Town
    (2024) Davis, Brandon; Kinnes, Irvin; Mguzulwa, Sisanda
    The Neighbourhood Watch (NW) is a pervasive phenomenon that has gained footholds in many countries around the world. South Africa is no exception and, in the case of Cape Town in the Western Cape Province, they have proven to be a popular choice among the members of civil society as a method of dealing with crime. In the Cape Flats region of Cape Town, conventional state policing agencies (namely SAPS) have failed to deal with the high rates of crime – one of the reasons for the popularity of NWs. Civil policing structures are by no means a new phenomenon in South Africa, and the concept of the NW has been in existence for decades, yet not much academic research has focused on their evolution over the years – particularly those that exist in the Cape Flats region. Using a nodal governance framework, specifically that of nodal policing, this dissertation explores the evolution of their roles, and the relationships or networks they formed (or lack thereof) over time in the battle to reduce crime and to create safe and secure communities. Indeed, numerous studies have been conducted on policing in South Africa for many decades, and some have focused on non-state policing structures in the country. In doing so, they have briefly discussed NWs, however there are few comprehensive studies that have focused solely on the NW and discussed how they have evolved over time. This study addresses that particular gap in the literature. A qualitative study was conducted and members of three different NWs on the Cape Flats located in different areas (two from the Athlone precinct and one from the Manenberg precinct) were interviewed in three separate focus group interviews. The NWs selected for this study were the Bridgetown and Silvertown NWs (Athlone precinct) and the Surrey Estate NW (Manenberg precinct). Importantly, a precinct is a defined district or region of a city which consists of multiple areas (South African National Treasury, 2014:np).
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    Extinctions: Past and Present Week 4 - Becoming human
    (2017-03-17) Chinsamy-Turan, Anusuya; Ackerman, Becky
    In this video, Professor Anusuya Chinsamy-Turan interviews Professor Becky Ackerman, a biological anthropologist, about how and when humans became such a dominant species. This is video 7 in Week 4 of the Extinctions: Past and Present MOOC.
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    Extinctions: Past and Present Week 4 - New dinosaur discoveries
    (2017-03-17) Chinsamy-Turan, Anusuya; Krupandan, Emil
    In this video, Professor Anusaya Chinsamy-Turan interviews Dr Emil Krupandan about some of the research he has done during his PhD to uncover new information about the early evolution and biology of the long neck dinosaurs. They discuss the characteristics of some dinosaur species in detail.
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    Large-scale perturbations on the brane and the isotropy of the cosmological singularity
    (2004) Goheer, Naureen; Dunsby, Peter K S; Coley, Alan; Bruni, Marco
    We present the complete set of propagation and constraint equations for the kinematic and non-local first order quantities which describe general linear inhomogeneous and anisotropic perturbations of a flat FRW braneworld with vanishing cosmological constant and decompose them in the standard way into their scalar, vector and tensor contributions. A detailed analysis of the perturbation dynamics is performed using dimensionless variables that are specially tailored for the different regimes of interest; namely, the low energy GR regime, the high energy regime and the dark energy regime. Tables are presented for the evolution of all the physical quantities, making it easy to do a detailed comparison of the past asymptotic behaviour of the perturbations of these models. We find results that exactly match those obtained in the analysis of the spatially inhomogeneous $G_{2}$ braneworld cosmologies presented recently; i.e., that isotropization towards the ${cal F}_b$ model occurs for $gamma > 4/3$.
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    Medicine and the Arts Week 3 - Art and play
    (2015-01-21) Solms, Mark
    In this video, neuropsychologist Mark Solms explains how, from a neuroscientific perspective, our innate drive to play might be an underlying evolutionary mechanism for testing real world interactions. He suggests that art is then an expression of the human instinct to play and artistic expression offers society ways of creatively representing meaning. This is the fifth video in Week 3 of the Medicine and the Arts Massive Open Online Course.
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    Morphology, evolution and taxonomy of Wachendorfia (Haemodoraceae)
    (1992) Helme, N E; Linder, H P
    Wachendorfia Burm. is a small genus endemic to the Cape Floral Region. Pour species are recognised in this study. Two species were originally described by Burman in 1757 and these were followed by numerous other descriptions of what is essentially one very variable species  (W. paniculaia Burm.). This variation is discussed and reasons are given as to why the recognition of formal infraspecific taxa is inappropriate. Formal taxonomic descriptions, distribution maps and a key to the species are provided. Rhizome morphology, leaf anatomy and pollen and seed coat structures were investigated and illustrations are provided. A cladogram was inferred and this is consistent with an ecological speciation model for the genus. The two species with the most restricted distribution (W. brachyandra W.F. Barker and W. pamfiora W.F. Barker) are considered to be the most recently evolved. Features of systematic and ecological interest (e.g. floral enantiomorphy) are discussed.
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    Reading scientific images: the iconography of evolution
    (2011) Mason, Richard; Morphet, Tony; Prosalendis, Sandra
    Visual literacy is the ability to read and understand images. While we are taught to read and write words at school, no focused attention is given to teaching the skills to read images other than as ‘art’ or attractive illustrations of the words we read in schools. This book about scientific visual literacy focuses on the most dynamic area of contemporary human discovery, the theory of evolution.
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    THE CENTRAL SLOPE OF DARK MATTER CORES IN DWARF GALAXIES: SIMULATIONS VERSUS THINGS
    (2011) Oh, Se-Heon; Brook, Chris; Governato, Fabio; Brinks, Elias; Mayer, Lucio; de Blok, W J G; Brooks, Alyson; Walter, Fabian
    We make a direct comparison of the derived dark matter (DM) distributions between hydrodynamical simulations of dwarf galaxies assuming ACDM cosmology and the observed dwarf galaxies sample from the THINGS survey in terms of (1) the rotation curve shape and (2) the logarithmic inner density slope a of mass density profiles. The simulations, which include the effect of baryonic feedback processes, such as gas cooling, star formation, cosmic UV background heating, and most importantly, physically motivated gas outflows driven by supernovae, form bulgeless galaxies with DM cores. We show that the stellar and baryonic mass is similar to that inferred from photometric and kinematic methods for galaxies of similar circular velocity. Analyzing the simulations in exactly the same way as the observational sample allows us to address directly the so-called cusp/core problem in the ACDM model. We show that the rotation curves of the simulated dwarf galaxies rise less steeply than cold dark matter rotation curves and are consistent with those of the THINGS dwarf galaxies. The mean value of the logarithmic inner density slopes alpha of the simulated galaxies' DM density profiles is similar to-0.4 +/- 0.1, which shows good agreement with alpha = -0.29 +/- 0.07 of the THINGS dwarf galaxies. The effect of non-circular motions is not significant enough to affect the results. This confirms that the baryonic feedback processes included in the simulations are efficiently able to make the initial cusps with alpha similar to-1.0 to -1.5 predicted by DM-only simulations shallower and induce DM halos with a central mass distribution similar to that observed in nearby dwarf galaxies.
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    The LOFAR Two-metre Sky Survey: I. Survey description and preliminary data release⋆
    (2017) Shimwell, T W; Röttgering, H J A; Best, P N; Williams, W L; Dijkema, T J; de Gasperin, F; Hardcastle, M J; Heald, G H; Hoang, D N; Horneffer, A; Intema, H; Mahony, E K; Mandal, S; Mechev, A P; Morabito, L; Oonk, J B R; Rafferty, D; Retana-Montenegro, E; Sabater, J; Tasse, C; van Weeren, R J; BrYggen, M; Brunetti, G; Chyży, K T; Conway, J E; Haverkorn, M; Jackson, N; Jarvis, M J; McKean, J P; Miley, G K; Morganti, R; White, G J
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